Coast Guard jet crash still a mystery as eight-month inquiry ends

The mystery surrounding Indian Coast Guard (ICG) Dornier plane flight CG791 has only intensified after the end of a prolonged inquiry.

Older questions about the plane's sudden disappearance and the discovery of its wreckage at the bottom of the Bay of Bengal have been replaced by new ones.

Flying at about 9,000 ft from Chennai on a routine mission, on a fairly well-lit evening of June 8 last year, the aircraft disappeared from the tracking radars at 9.24pm.

The plane, a Dornier, disappeared from tracking radars on June 8 last year. (Picture for representation only.)

The last recorded position of the plane was 32 miles north east of Karaikal, near Puducherry.

The plane, CG DOR 791, was to return to Chennai at 10pm. Initial information stated that the International Maritime Satellite (INMARSAT) terminal on board powered off.

The ICG’s Board of Inquiry (BOI) report pins the cause of the crash on a device known as Attitude and Heading Reference Unit (AHRU).

The AHRU is said to be the single biggest aid to a crew flying at night over sea.

A top IAF officer explained: “We found that the power supply to the AHRU stopped suddenly. When that happened, the crew lost control. Why the power went off in the first place is not something we have been able to ascertain.”

In reaching this conclusion, the ICG relied extensively on the Flight Data Recorder (FDR) which was retrieved.

What complicated matters was that the Cockpit Voice Recorder (CVR) was completely smashed.

While the ICG has been unable to establish the cause, it is certain there was no sabotage. The BOI findings don’t blame any individual or organisation.

The wreckage and mortal remains of the three-member crew were retrieved following an unprecedented 36-day search, during which it remained deposited at a depth of 990m at sea. The salvage itself was said to be one of the most intense in India’s maritime history.

One reason why the crash raised eyebrows was because of the plane involved. The Dornier, licence-made in India by the Hindustan Aeronautics Limited (HAL), is among the most stable platforms in military aviation.

Gopal Sutar, Chief of Media Communications, HAL said: “We are not privy to the report and hence, cannot comment. However, there have been no previous incidents or crashes that directly attribute to AHRU.”

What has further perplexed observers is the role of the standby systems.

“The way any armed force works is that...if plan A fails, there is always B and even C. I am unable to digest the ICG’s response,” said a senior officer.